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authorLinus Torvalds <torvalds@linux-foundation.org>2009-03-27 17:48:34 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-03-27 17:48:34 -0400
commit2c9e15a011c55ff96b2b8d2b126d1b9a96abba20 (patch)
tree6d9b27a07f88ad4509dcd86aa74a2cdecd0d5f4b /fs/quota/dquot.c
parent805de022b100bcf796860fe88d7db4164066d1c3 (diff)
parentc16831b4cc9b0805adf8ca3001752a7ec10a17bf (diff)
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6: (27 commits) ext2: Zero our b_size in ext2_quota_read() trivial: fix typos/grammar errors in fs/Kconfig quota: Coding style fixes quota: Remove superfluous inlines quota: Remove uppercase aliases for quota functions. nfsd: Use lowercase names of quota functions jfs: Use lowercase names of quota functions udf: Use lowercase names of quota functions ufs: Use lowercase names of quota functions reiserfs: Use lowercase names of quota functions ext4: Use lowercase names of quota functions ext3: Use lowercase names of quota functions ext2: Use lowercase names of quota functions ramfs: Remove quota call vfs: Use lowercase names of quota functions quota: Remove dqbuf_t and other cleanups quota: Remove NODQUOT macro quota: Make global quota locks cacheline aligned quota: Move quota files into separate directory ext4: quota reservation for delayed allocation ...
Diffstat (limited to 'fs/quota/dquot.c')
-rw-r--r--fs/quota/dquot.c2611
1 files changed, 2611 insertions, 0 deletions
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
new file mode 100644
index 000000000000..eb938015bd91
--- /dev/null
+++ b/fs/quota/dquot.c
@@ -0,0 +1,2611 @@
1/*
2 * Implementation of the diskquota system for the LINUX operating system. QUOTA
3 * is implemented using the BSD system call interface as the means of
4 * communication with the user level. This file contains the generic routines
5 * called by the different filesystems on allocation of an inode or block.
6 * These routines take care of the administration needed to have a consistent
7 * diskquota tracking system. The ideas of both user and group quotas are based
8 * on the Melbourne quota system as used on BSD derived systems. The internal
9 * implementation is based on one of the several variants of the LINUX
10 * inode-subsystem with added complexity of the diskquota system.
11 *
12 * Author: Marco van Wieringen <mvw@planets.elm.net>
13 *
14 * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
15 *
16 * Revised list management to avoid races
17 * -- Bill Hawes, <whawes@star.net>, 9/98
18 *
19 * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
20 * As the consequence the locking was moved from dquot_decr_...(),
21 * dquot_incr_...() to calling functions.
22 * invalidate_dquots() now writes modified dquots.
23 * Serialized quota_off() and quota_on() for mount point.
24 * Fixed a few bugs in grow_dquots().
25 * Fixed deadlock in write_dquot() - we no longer account quotas on
26 * quota files
27 * remove_dquot_ref() moved to inode.c - it now traverses through inodes
28 * add_dquot_ref() restarts after blocking
29 * Added check for bogus uid and fixed check for group in quotactl.
30 * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
31 *
32 * Used struct list_head instead of own list struct
33 * Invalidation of referenced dquots is no longer possible
34 * Improved free_dquots list management
35 * Quota and i_blocks are now updated in one place to avoid races
36 * Warnings are now delayed so we won't block in critical section
37 * Write updated not to require dquot lock
38 * Jan Kara, <jack@suse.cz>, 9/2000
39 *
40 * Added dynamic quota structure allocation
41 * Jan Kara <jack@suse.cz> 12/2000
42 *
43 * Rewritten quota interface. Implemented new quota format and
44 * formats registering.
45 * Jan Kara, <jack@suse.cz>, 2001,2002
46 *
47 * New SMP locking.
48 * Jan Kara, <jack@suse.cz>, 10/2002
49 *
50 * Added journalled quota support, fix lock inversion problems
51 * Jan Kara, <jack@suse.cz>, 2003,2004
52 *
53 * (C) Copyright 1994 - 1997 Marco van Wieringen
54 */
55
56#include <linux/errno.h>
57#include <linux/kernel.h>
58#include <linux/fs.h>
59#include <linux/mount.h>
60#include <linux/mm.h>
61#include <linux/time.h>
62#include <linux/types.h>
63#include <linux/string.h>
64#include <linux/fcntl.h>
65#include <linux/stat.h>
66#include <linux/tty.h>
67#include <linux/file.h>
68#include <linux/slab.h>
69#include <linux/sysctl.h>
70#include <linux/init.h>
71#include <linux/module.h>
72#include <linux/proc_fs.h>
73#include <linux/security.h>
74#include <linux/kmod.h>
75#include <linux/namei.h>
76#include <linux/buffer_head.h>
77#include <linux/capability.h>
78#include <linux/quotaops.h>
79#include <linux/writeback.h> /* for inode_lock, oddly enough.. */
80#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
81#include <net/netlink.h>
82#include <net/genetlink.h>
83#endif
84
85#include <asm/uaccess.h>
86
87#define __DQUOT_PARANOIA
88
89/*
90 * There are three quota SMP locks. dq_list_lock protects all lists with quotas
91 * and quota formats, dqstats structure containing statistics about the lists
92 * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
93 * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
94 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
95 * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects
96 * modifications of quota state (on quotaon and quotaoff) and readers who care
97 * about latest values take it as well.
98 *
99 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock,
100 * dq_list_lock > dq_state_lock
101 *
102 * Note that some things (eg. sb pointer, type, id) doesn't change during
103 * the life of the dquot structure and so needn't to be protected by a lock
104 *
105 * Any operation working on dquots via inode pointers must hold dqptr_sem. If
106 * operation is just reading pointers from inode (or not using them at all) the
107 * read lock is enough. If pointers are altered function must hold write lock
108 * (these locking rules also apply for S_NOQUOTA flag in the inode - note that
109 * for altering the flag i_mutex is also needed).
110 *
111 * Each dquot has its dq_lock mutex. Locked dquots might not be referenced
112 * from inodes (dquot_alloc_space() and such don't check the dq_lock).
113 * Currently dquot is locked only when it is being read to memory (or space for
114 * it is being allocated) on the first dqget() and when it is being released on
115 * the last dqput(). The allocation and release oparations are serialized by
116 * the dq_lock and by checking the use count in dquot_release(). Write
117 * operations on dquots don't hold dq_lock as they copy data under dq_data_lock
118 * spinlock to internal buffers before writing.
119 *
120 * Lock ordering (including related VFS locks) is the following:
121 * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock >
122 * dqio_mutex
123 * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem >
124 * dqptr_sem. But filesystem has to count with the fact that functions such as
125 * dquot_alloc_space() acquire dqptr_sem and they usually have to be called
126 * from inside a transaction to keep filesystem consistency after a crash. Also
127 * filesystems usually want to do some IO on dquot from ->mark_dirty which is
128 * called with dqptr_sem held.
129 * i_mutex on quota files is special (it's below dqio_mutex)
130 */
131
132static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock);
133static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
134__cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);
135EXPORT_SYMBOL(dq_data_lock);
136
137static char *quotatypes[] = INITQFNAMES;
138static struct quota_format_type *quota_formats; /* List of registered formats */
139static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
140
141/* SLAB cache for dquot structures */
142static struct kmem_cache *dquot_cachep;
143
144int register_quota_format(struct quota_format_type *fmt)
145{
146 spin_lock(&dq_list_lock);
147 fmt->qf_next = quota_formats;
148 quota_formats = fmt;
149 spin_unlock(&dq_list_lock);
150 return 0;
151}
152EXPORT_SYMBOL(register_quota_format);
153
154void unregister_quota_format(struct quota_format_type *fmt)
155{
156 struct quota_format_type **actqf;
157
158 spin_lock(&dq_list_lock);
159 for (actqf = &quota_formats; *actqf && *actqf != fmt;
160 actqf = &(*actqf)->qf_next)
161 ;
162 if (*actqf)
163 *actqf = (*actqf)->qf_next;
164 spin_unlock(&dq_list_lock);
165}
166EXPORT_SYMBOL(unregister_quota_format);
167
168static struct quota_format_type *find_quota_format(int id)
169{
170 struct quota_format_type *actqf;
171
172 spin_lock(&dq_list_lock);
173 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
174 actqf = actqf->qf_next)
175 ;
176 if (!actqf || !try_module_get(actqf->qf_owner)) {
177 int qm;
178
179 spin_unlock(&dq_list_lock);
180
181 for (qm = 0; module_names[qm].qm_fmt_id &&
182 module_names[qm].qm_fmt_id != id; qm++)
183 ;
184 if (!module_names[qm].qm_fmt_id ||
185 request_module(module_names[qm].qm_mod_name))
186 return NULL;
187
188 spin_lock(&dq_list_lock);
189 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
190 actqf = actqf->qf_next)
191 ;
192 if (actqf && !try_module_get(actqf->qf_owner))
193 actqf = NULL;
194 }
195 spin_unlock(&dq_list_lock);
196 return actqf;
197}
198
199static void put_quota_format(struct quota_format_type *fmt)
200{
201 module_put(fmt->qf_owner);
202}
203
204/*
205 * Dquot List Management:
206 * The quota code uses three lists for dquot management: the inuse_list,
207 * free_dquots, and dquot_hash[] array. A single dquot structure may be
208 * on all three lists, depending on its current state.
209 *
210 * All dquots are placed to the end of inuse_list when first created, and this
211 * list is used for invalidate operation, which must look at every dquot.
212 *
213 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
214 * and this list is searched whenever we need an available dquot. Dquots are
215 * removed from the list as soon as they are used again, and
216 * dqstats.free_dquots gives the number of dquots on the list. When
217 * dquot is invalidated it's completely released from memory.
218 *
219 * Dquots with a specific identity (device, type and id) are placed on
220 * one of the dquot_hash[] hash chains. The provides an efficient search
221 * mechanism to locate a specific dquot.
222 */
223
224static LIST_HEAD(inuse_list);
225static LIST_HEAD(free_dquots);
226static unsigned int dq_hash_bits, dq_hash_mask;
227static struct hlist_head *dquot_hash;
228
229struct dqstats dqstats;
230EXPORT_SYMBOL(dqstats);
231
232static inline unsigned int
233hashfn(const struct super_block *sb, unsigned int id, int type)
234{
235 unsigned long tmp;
236
237 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
238 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
239}
240
241/*
242 * Following list functions expect dq_list_lock to be held
243 */
244static inline void insert_dquot_hash(struct dquot *dquot)
245{
246 struct hlist_head *head;
247 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
248 hlist_add_head(&dquot->dq_hash, head);
249}
250
251static inline void remove_dquot_hash(struct dquot *dquot)
252{
253 hlist_del_init(&dquot->dq_hash);
254}
255
256static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,
257 unsigned int id, int type)
258{
259 struct hlist_node *node;
260 struct dquot *dquot;
261
262 hlist_for_each (node, dquot_hash+hashent) {
263 dquot = hlist_entry(node, struct dquot, dq_hash);
264 if (dquot->dq_sb == sb && dquot->dq_id == id &&
265 dquot->dq_type == type)
266 return dquot;
267 }
268 return NULL;
269}
270
271/* Add a dquot to the tail of the free list */
272static inline void put_dquot_last(struct dquot *dquot)
273{
274 list_add_tail(&dquot->dq_free, &free_dquots);
275 dqstats.free_dquots++;
276}
277
278static inline void remove_free_dquot(struct dquot *dquot)
279{
280 if (list_empty(&dquot->dq_free))
281 return;
282 list_del_init(&dquot->dq_free);
283 dqstats.free_dquots--;
284}
285
286static inline void put_inuse(struct dquot *dquot)
287{
288 /* We add to the back of inuse list so we don't have to restart
289 * when traversing this list and we block */
290 list_add_tail(&dquot->dq_inuse, &inuse_list);
291 dqstats.allocated_dquots++;
292}
293
294static inline void remove_inuse(struct dquot *dquot)
295{
296 dqstats.allocated_dquots--;
297 list_del(&dquot->dq_inuse);
298}
299/*
300 * End of list functions needing dq_list_lock
301 */
302
303static void wait_on_dquot(struct dquot *dquot)
304{
305 mutex_lock(&dquot->dq_lock);
306 mutex_unlock(&dquot->dq_lock);
307}
308
309static inline int dquot_dirty(struct dquot *dquot)
310{
311 return test_bit(DQ_MOD_B, &dquot->dq_flags);
312}
313
314static inline int mark_dquot_dirty(struct dquot *dquot)
315{
316 return dquot->dq_sb->dq_op->mark_dirty(dquot);
317}
318
319int dquot_mark_dquot_dirty(struct dquot *dquot)
320{
321 spin_lock(&dq_list_lock);
322 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
323 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
324 info[dquot->dq_type].dqi_dirty_list);
325 spin_unlock(&dq_list_lock);
326 return 0;
327}
328EXPORT_SYMBOL(dquot_mark_dquot_dirty);
329
330/* This function needs dq_list_lock */
331static inline int clear_dquot_dirty(struct dquot *dquot)
332{
333 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
334 return 0;
335 list_del_init(&dquot->dq_dirty);
336 return 1;
337}
338
339void mark_info_dirty(struct super_block *sb, int type)
340{
341 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
342}
343EXPORT_SYMBOL(mark_info_dirty);
344
345/*
346 * Read dquot from disk and alloc space for it
347 */
348
349int dquot_acquire(struct dquot *dquot)
350{
351 int ret = 0, ret2 = 0;
352 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
353
354 mutex_lock(&dquot->dq_lock);
355 mutex_lock(&dqopt->dqio_mutex);
356 if (!test_bit(DQ_READ_B, &dquot->dq_flags))
357 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
358 if (ret < 0)
359 goto out_iolock;
360 set_bit(DQ_READ_B, &dquot->dq_flags);
361 /* Instantiate dquot if needed */
362 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
363 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
364 /* Write the info if needed */
365 if (info_dirty(&dqopt->info[dquot->dq_type])) {
366 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
367 dquot->dq_sb, dquot->dq_type);
368 }
369 if (ret < 0)
370 goto out_iolock;
371 if (ret2 < 0) {
372 ret = ret2;
373 goto out_iolock;
374 }
375 }
376 set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
377out_iolock:
378 mutex_unlock(&dqopt->dqio_mutex);
379 mutex_unlock(&dquot->dq_lock);
380 return ret;
381}
382EXPORT_SYMBOL(dquot_acquire);
383
384/*
385 * Write dquot to disk
386 */
387int dquot_commit(struct dquot *dquot)
388{
389 int ret = 0, ret2 = 0;
390 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
391
392 mutex_lock(&dqopt->dqio_mutex);
393 spin_lock(&dq_list_lock);
394 if (!clear_dquot_dirty(dquot)) {
395 spin_unlock(&dq_list_lock);
396 goto out_sem;
397 }
398 spin_unlock(&dq_list_lock);
399 /* Inactive dquot can be only if there was error during read/init
400 * => we have better not writing it */
401 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
402 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
403 if (info_dirty(&dqopt->info[dquot->dq_type])) {
404 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
405 dquot->dq_sb, dquot->dq_type);
406 }
407 if (ret >= 0)
408 ret = ret2;
409 }
410out_sem:
411 mutex_unlock(&dqopt->dqio_mutex);
412 return ret;
413}
414EXPORT_SYMBOL(dquot_commit);
415
416/*
417 * Release dquot
418 */
419int dquot_release(struct dquot *dquot)
420{
421 int ret = 0, ret2 = 0;
422 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
423
424 mutex_lock(&dquot->dq_lock);
425 /* Check whether we are not racing with some other dqget() */
426 if (atomic_read(&dquot->dq_count) > 1)
427 goto out_dqlock;
428 mutex_lock(&dqopt->dqio_mutex);
429 if (dqopt->ops[dquot->dq_type]->release_dqblk) {
430 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
431 /* Write the info */
432 if (info_dirty(&dqopt->info[dquot->dq_type])) {
433 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
434 dquot->dq_sb, dquot->dq_type);
435 }
436 if (ret >= 0)
437 ret = ret2;
438 }
439 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
440 mutex_unlock(&dqopt->dqio_mutex);
441out_dqlock:
442 mutex_unlock(&dquot->dq_lock);
443 return ret;
444}
445EXPORT_SYMBOL(dquot_release);
446
447void dquot_destroy(struct dquot *dquot)
448{
449 kmem_cache_free(dquot_cachep, dquot);
450}
451EXPORT_SYMBOL(dquot_destroy);
452
453static inline void do_destroy_dquot(struct dquot *dquot)
454{
455 dquot->dq_sb->dq_op->destroy_dquot(dquot);
456}
457
458/* Invalidate all dquots on the list. Note that this function is called after
459 * quota is disabled and pointers from inodes removed so there cannot be new
460 * quota users. There can still be some users of quotas due to inodes being
461 * just deleted or pruned by prune_icache() (those are not attached to any
462 * list) or parallel quotactl call. We have to wait for such users.
463 */
464static void invalidate_dquots(struct super_block *sb, int type)
465{
466 struct dquot *dquot, *tmp;
467
468restart:
469 spin_lock(&dq_list_lock);
470 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
471 if (dquot->dq_sb != sb)
472 continue;
473 if (dquot->dq_type != type)
474 continue;
475 /* Wait for dquot users */
476 if (atomic_read(&dquot->dq_count)) {
477 DEFINE_WAIT(wait);
478
479 atomic_inc(&dquot->dq_count);
480 prepare_to_wait(&dquot->dq_wait_unused, &wait,
481 TASK_UNINTERRUPTIBLE);
482 spin_unlock(&dq_list_lock);
483 /* Once dqput() wakes us up, we know it's time to free
484 * the dquot.
485 * IMPORTANT: we rely on the fact that there is always
486 * at most one process waiting for dquot to free.
487 * Otherwise dq_count would be > 1 and we would never
488 * wake up.
489 */
490 if (atomic_read(&dquot->dq_count) > 1)
491 schedule();
492 finish_wait(&dquot->dq_wait_unused, &wait);
493 dqput(dquot);
494 /* At this moment dquot() need not exist (it could be
495 * reclaimed by prune_dqcache(). Hence we must
496 * restart. */
497 goto restart;
498 }
499 /*
500 * Quota now has no users and it has been written on last
501 * dqput()
502 */
503 remove_dquot_hash(dquot);
504 remove_free_dquot(dquot);
505 remove_inuse(dquot);
506 do_destroy_dquot(dquot);
507 }
508 spin_unlock(&dq_list_lock);
509}
510
511/* Call callback for every active dquot on given filesystem */
512int dquot_scan_active(struct super_block *sb,
513 int (*fn)(struct dquot *dquot, unsigned long priv),
514 unsigned long priv)
515{
516 struct dquot *dquot, *old_dquot = NULL;
517 int ret = 0;
518
519 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
520 spin_lock(&dq_list_lock);
521 list_for_each_entry(dquot, &inuse_list, dq_inuse) {
522 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
523 continue;
524 if (dquot->dq_sb != sb)
525 continue;
526 /* Now we have active dquot so we can just increase use count */
527 atomic_inc(&dquot->dq_count);
528 dqstats.lookups++;
529 spin_unlock(&dq_list_lock);
530 dqput(old_dquot);
531 old_dquot = dquot;
532 ret = fn(dquot, priv);
533 if (ret < 0)
534 goto out;
535 spin_lock(&dq_list_lock);
536 /* We are safe to continue now because our dquot could not
537 * be moved out of the inuse list while we hold the reference */
538 }
539 spin_unlock(&dq_list_lock);
540out:
541 dqput(old_dquot);
542 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
543 return ret;
544}
545EXPORT_SYMBOL(dquot_scan_active);
546
547int vfs_quota_sync(struct super_block *sb, int type)
548{
549 struct list_head *dirty;
550 struct dquot *dquot;
551 struct quota_info *dqopt = sb_dqopt(sb);
552 int cnt;
553
554 mutex_lock(&dqopt->dqonoff_mutex);
555 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
556 if (type != -1 && cnt != type)
557 continue;
558 if (!sb_has_quota_active(sb, cnt))
559 continue;
560 spin_lock(&dq_list_lock);
561 dirty = &dqopt->info[cnt].dqi_dirty_list;
562 while (!list_empty(dirty)) {
563 dquot = list_first_entry(dirty, struct dquot,
564 dq_dirty);
565 /* Dirty and inactive can be only bad dquot... */
566 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
567 clear_dquot_dirty(dquot);
568 continue;
569 }
570 /* Now we have active dquot from which someone is
571 * holding reference so we can safely just increase
572 * use count */
573 atomic_inc(&dquot->dq_count);
574 dqstats.lookups++;
575 spin_unlock(&dq_list_lock);
576 sb->dq_op->write_dquot(dquot);
577 dqput(dquot);
578 spin_lock(&dq_list_lock);
579 }
580 spin_unlock(&dq_list_lock);
581 }
582
583 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
584 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
585 && info_dirty(&dqopt->info[cnt]))
586 sb->dq_op->write_info(sb, cnt);
587 spin_lock(&dq_list_lock);
588 dqstats.syncs++;
589 spin_unlock(&dq_list_lock);
590 mutex_unlock(&dqopt->dqonoff_mutex);
591
592 return 0;
593}
594EXPORT_SYMBOL(vfs_quota_sync);
595
596/* Free unused dquots from cache */
597static void prune_dqcache(int count)
598{
599 struct list_head *head;
600 struct dquot *dquot;
601
602 head = free_dquots.prev;
603 while (head != &free_dquots && count) {
604 dquot = list_entry(head, struct dquot, dq_free);
605 remove_dquot_hash(dquot);
606 remove_free_dquot(dquot);
607 remove_inuse(dquot);
608 do_destroy_dquot(dquot);
609 count--;
610 head = free_dquots.prev;
611 }
612}
613
614/*
615 * This is called from kswapd when we think we need some
616 * more memory
617 */
618
619static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
620{
621 if (nr) {
622 spin_lock(&dq_list_lock);
623 prune_dqcache(nr);
624 spin_unlock(&dq_list_lock);
625 }
626 return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
627}
628
629static struct shrinker dqcache_shrinker = {
630 .shrink = shrink_dqcache_memory,
631 .seeks = DEFAULT_SEEKS,
632};
633
634/*
635 * Put reference to dquot
636 * NOTE: If you change this function please check whether dqput_blocks() works right...
637 */
638void dqput(struct dquot *dquot)
639{
640 int ret;
641
642 if (!dquot)
643 return;
644#ifdef __DQUOT_PARANOIA
645 if (!atomic_read(&dquot->dq_count)) {
646 printk("VFS: dqput: trying to free free dquot\n");
647 printk("VFS: device %s, dquot of %s %d\n",
648 dquot->dq_sb->s_id,
649 quotatypes[dquot->dq_type],
650 dquot->dq_id);
651 BUG();
652 }
653#endif
654
655 spin_lock(&dq_list_lock);
656 dqstats.drops++;
657 spin_unlock(&dq_list_lock);
658we_slept:
659 spin_lock(&dq_list_lock);
660 if (atomic_read(&dquot->dq_count) > 1) {
661 /* We have more than one user... nothing to do */
662 atomic_dec(&dquot->dq_count);
663 /* Releasing dquot during quotaoff phase? */
664 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) &&
665 atomic_read(&dquot->dq_count) == 1)
666 wake_up(&dquot->dq_wait_unused);
667 spin_unlock(&dq_list_lock);
668 return;
669 }
670 /* Need to release dquot? */
671 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
672 spin_unlock(&dq_list_lock);
673 /* Commit dquot before releasing */
674 ret = dquot->dq_sb->dq_op->write_dquot(dquot);
675 if (ret < 0) {
676 printk(KERN_ERR "VFS: cannot write quota structure on "
677 "device %s (error %d). Quota may get out of "
678 "sync!\n", dquot->dq_sb->s_id, ret);
679 /*
680 * We clear dirty bit anyway, so that we avoid
681 * infinite loop here
682 */
683 spin_lock(&dq_list_lock);
684 clear_dquot_dirty(dquot);
685 spin_unlock(&dq_list_lock);
686 }
687 goto we_slept;
688 }
689 /* Clear flag in case dquot was inactive (something bad happened) */
690 clear_dquot_dirty(dquot);
691 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
692 spin_unlock(&dq_list_lock);
693 dquot->dq_sb->dq_op->release_dquot(dquot);
694 goto we_slept;
695 }
696 atomic_dec(&dquot->dq_count);
697#ifdef __DQUOT_PARANOIA
698 /* sanity check */
699 BUG_ON(!list_empty(&dquot->dq_free));
700#endif
701 put_dquot_last(dquot);
702 spin_unlock(&dq_list_lock);
703}
704EXPORT_SYMBOL(dqput);
705
706struct dquot *dquot_alloc(struct super_block *sb, int type)
707{
708 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
709}
710EXPORT_SYMBOL(dquot_alloc);
711
712static struct dquot *get_empty_dquot(struct super_block *sb, int type)
713{
714 struct dquot *dquot;
715
716 dquot = sb->dq_op->alloc_dquot(sb, type);
717 if(!dquot)
718 return NULL;
719
720 mutex_init(&dquot->dq_lock);
721 INIT_LIST_HEAD(&dquot->dq_free);
722 INIT_LIST_HEAD(&dquot->dq_inuse);
723 INIT_HLIST_NODE(&dquot->dq_hash);
724 INIT_LIST_HEAD(&dquot->dq_dirty);
725 init_waitqueue_head(&dquot->dq_wait_unused);
726 dquot->dq_sb = sb;
727 dquot->dq_type = type;
728 atomic_set(&dquot->dq_count, 1);
729
730 return dquot;
731}
732
733/*
734 * Get reference to dquot
735 *
736 * Locking is slightly tricky here. We are guarded from parallel quotaoff()
737 * destroying our dquot by:
738 * a) checking for quota flags under dq_list_lock and
739 * b) getting a reference to dquot before we release dq_list_lock
740 */
741struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
742{
743 unsigned int hashent = hashfn(sb, id, type);
744 struct dquot *dquot = NULL, *empty = NULL;
745
746 if (!sb_has_quota_active(sb, type))
747 return NULL;
748we_slept:
749 spin_lock(&dq_list_lock);
750 spin_lock(&dq_state_lock);
751 if (!sb_has_quota_active(sb, type)) {
752 spin_unlock(&dq_state_lock);
753 spin_unlock(&dq_list_lock);
754 goto out;
755 }
756 spin_unlock(&dq_state_lock);
757
758 dquot = find_dquot(hashent, sb, id, type);
759 if (!dquot) {
760 if (!empty) {
761 spin_unlock(&dq_list_lock);
762 empty = get_empty_dquot(sb, type);
763 if (!empty)
764 schedule(); /* Try to wait for a moment... */
765 goto we_slept;
766 }
767 dquot = empty;
768 empty = NULL;
769 dquot->dq_id = id;
770 /* all dquots go on the inuse_list */
771 put_inuse(dquot);
772 /* hash it first so it can be found */
773 insert_dquot_hash(dquot);
774 dqstats.lookups++;
775 spin_unlock(&dq_list_lock);
776 } else {
777 if (!atomic_read(&dquot->dq_count))
778 remove_free_dquot(dquot);
779 atomic_inc(&dquot->dq_count);
780 dqstats.cache_hits++;
781 dqstats.lookups++;
782 spin_unlock(&dq_list_lock);
783 }
784 /* Wait for dq_lock - after this we know that either dquot_release() is
785 * already finished or it will be canceled due to dq_count > 1 test */
786 wait_on_dquot(dquot);
787 /* Read the dquot / allocate space in quota file */
788 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) &&
789 sb->dq_op->acquire_dquot(dquot) < 0) {
790 dqput(dquot);
791 dquot = NULL;
792 goto out;
793 }
794#ifdef __DQUOT_PARANOIA
795 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
796#endif
797out:
798 if (empty)
799 do_destroy_dquot(empty);
800
801 return dquot;
802}
803EXPORT_SYMBOL(dqget);
804
805static int dqinit_needed(struct inode *inode, int type)
806{
807 int cnt;
808
809 if (IS_NOQUOTA(inode))
810 return 0;
811 if (type != -1)
812 return !inode->i_dquot[type];
813 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
814 if (!inode->i_dquot[cnt])
815 return 1;
816 return 0;
817}
818
819/* This routine is guarded by dqonoff_mutex mutex */
820static void add_dquot_ref(struct super_block *sb, int type)
821{
822 struct inode *inode, *old_inode = NULL;
823
824 spin_lock(&inode_lock);
825 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
826 if (!atomic_read(&inode->i_writecount))
827 continue;
828 if (!dqinit_needed(inode, type))
829 continue;
830 if (inode->i_state & (I_FREEING|I_WILL_FREE))
831 continue;
832
833 __iget(inode);
834 spin_unlock(&inode_lock);
835
836 iput(old_inode);
837 sb->dq_op->initialize(inode, type);
838 /* We hold a reference to 'inode' so it couldn't have been
839 * removed from s_inodes list while we dropped the inode_lock.
840 * We cannot iput the inode now as we can be holding the last
841 * reference and we cannot iput it under inode_lock. So we
842 * keep the reference and iput it later. */
843 old_inode = inode;
844 spin_lock(&inode_lock);
845 }
846 spin_unlock(&inode_lock);
847 iput(old_inode);
848}
849
850/*
851 * Return 0 if dqput() won't block.
852 * (note that 1 doesn't necessarily mean blocking)
853 */
854static inline int dqput_blocks(struct dquot *dquot)
855{
856 if (atomic_read(&dquot->dq_count) <= 1)
857 return 1;
858 return 0;
859}
860
861/*
862 * Remove references to dquots from inode and add dquot to list for freeing
863 * if we have the last referece to dquot
864 * We can't race with anybody because we hold dqptr_sem for writing...
865 */
866static int remove_inode_dquot_ref(struct inode *inode, int type,
867 struct list_head *tofree_head)
868{
869 struct dquot *dquot = inode->i_dquot[type];
870
871 inode->i_dquot[type] = NULL;
872 if (dquot) {
873 if (dqput_blocks(dquot)) {
874#ifdef __DQUOT_PARANOIA
875 if (atomic_read(&dquot->dq_count) != 1)
876 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
877#endif
878 spin_lock(&dq_list_lock);
879 /* As dquot must have currently users it can't be on
880 * the free list... */
881 list_add(&dquot->dq_free, tofree_head);
882 spin_unlock(&dq_list_lock);
883 return 1;
884 }
885 else
886 dqput(dquot); /* We have guaranteed we won't block */
887 }
888 return 0;
889}
890
891/*
892 * Free list of dquots
893 * Dquots are removed from inodes and no new references can be got so we are
894 * the only ones holding reference
895 */
896static void put_dquot_list(struct list_head *tofree_head)
897{
898 struct list_head *act_head;
899 struct dquot *dquot;
900
901 act_head = tofree_head->next;
902 while (act_head != tofree_head) {
903 dquot = list_entry(act_head, struct dquot, dq_free);
904 act_head = act_head->next;
905 /* Remove dquot from the list so we won't have problems... */
906 list_del_init(&dquot->dq_free);
907 dqput(dquot);
908 }
909}
910
911static void remove_dquot_ref(struct super_block *sb, int type,
912 struct list_head *tofree_head)
913{
914 struct inode *inode;
915
916 spin_lock(&inode_lock);
917 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
918 if (!IS_NOQUOTA(inode))
919 remove_inode_dquot_ref(inode, type, tofree_head);
920 }
921 spin_unlock(&inode_lock);
922}
923
924/* Gather all references from inodes and drop them */
925static void drop_dquot_ref(struct super_block *sb, int type)
926{
927 LIST_HEAD(tofree_head);
928
929 if (sb->dq_op) {
930 down_write(&sb_dqopt(sb)->dqptr_sem);
931 remove_dquot_ref(sb, type, &tofree_head);
932 up_write(&sb_dqopt(sb)->dqptr_sem);
933 put_dquot_list(&tofree_head);
934 }
935}
936
937static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number)
938{
939 dquot->dq_dqb.dqb_curinodes += number;
940}
941
942static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
943{
944 dquot->dq_dqb.dqb_curspace += number;
945}
946
947static inline void dquot_resv_space(struct dquot *dquot, qsize_t number)
948{
949 dquot->dq_dqb.dqb_rsvspace += number;
950}
951
952/*
953 * Claim reserved quota space
954 */
955static void dquot_claim_reserved_space(struct dquot *dquot,
956 qsize_t number)
957{
958 WARN_ON(dquot->dq_dqb.dqb_rsvspace < number);
959 dquot->dq_dqb.dqb_curspace += number;
960 dquot->dq_dqb.dqb_rsvspace -= number;
961}
962
963static inline
964void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
965{
966 dquot->dq_dqb.dqb_rsvspace -= number;
967}
968
969static void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
970{
971 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
972 dquot->dq_dqb.dqb_curinodes >= number)
973 dquot->dq_dqb.dqb_curinodes -= number;
974 else
975 dquot->dq_dqb.dqb_curinodes = 0;
976 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
977 dquot->dq_dqb.dqb_itime = (time_t) 0;
978 clear_bit(DQ_INODES_B, &dquot->dq_flags);
979}
980
981static void dquot_decr_space(struct dquot *dquot, qsize_t number)
982{
983 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
984 dquot->dq_dqb.dqb_curspace >= number)
985 dquot->dq_dqb.dqb_curspace -= number;
986 else
987 dquot->dq_dqb.dqb_curspace = 0;
988 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
989 dquot->dq_dqb.dqb_btime = (time_t) 0;
990 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
991}
992
993static int warning_issued(struct dquot *dquot, const int warntype)
994{
995 int flag = (warntype == QUOTA_NL_BHARDWARN ||
996 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
997 ((warntype == QUOTA_NL_IHARDWARN ||
998 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
999
1000 if (!flag)
1001 return 0;
1002 return test_and_set_bit(flag, &dquot->dq_flags);
1003}
1004
1005#ifdef CONFIG_PRINT_QUOTA_WARNING
1006static int flag_print_warnings = 1;
1007
1008static int need_print_warning(struct dquot *dquot)
1009{
1010 if (!flag_print_warnings)
1011 return 0;
1012
1013 switch (dquot->dq_type) {
1014 case USRQUOTA:
1015 return current_fsuid() == dquot->dq_id;
1016 case GRPQUOTA:
1017 return in_group_p(dquot->dq_id);
1018 }
1019 return 0;
1020}
1021
1022/* Print warning to user which exceeded quota */
1023static void print_warning(struct dquot *dquot, const int warntype)
1024{
1025 char *msg = NULL;
1026 struct tty_struct *tty;
1027
1028 if (warntype == QUOTA_NL_IHARDBELOW ||
1029 warntype == QUOTA_NL_ISOFTBELOW ||
1030 warntype == QUOTA_NL_BHARDBELOW ||
1031 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot))
1032 return;
1033
1034 tty = get_current_tty();
1035 if (!tty)
1036 return;
1037 tty_write_message(tty, dquot->dq_sb->s_id);
1038 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
1039 tty_write_message(tty, ": warning, ");
1040 else
1041 tty_write_message(tty, ": write failed, ");
1042 tty_write_message(tty, quotatypes[dquot->dq_type]);
1043 switch (warntype) {
1044 case QUOTA_NL_IHARDWARN:
1045 msg = " file limit reached.\r\n";
1046 break;
1047 case QUOTA_NL_ISOFTLONGWARN:
1048 msg = " file quota exceeded too long.\r\n";
1049 break;
1050 case QUOTA_NL_ISOFTWARN:
1051 msg = " file quota exceeded.\r\n";
1052 break;
1053 case QUOTA_NL_BHARDWARN:
1054 msg = " block limit reached.\r\n";
1055 break;
1056 case QUOTA_NL_BSOFTLONGWARN:
1057 msg = " block quota exceeded too long.\r\n";
1058 break;
1059 case QUOTA_NL_BSOFTWARN:
1060 msg = " block quota exceeded.\r\n";
1061 break;
1062 }
1063 tty_write_message(tty, msg);
1064 tty_kref_put(tty);
1065}
1066#endif
1067
1068#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
1069
1070/* Netlink family structure for quota */
1071static struct genl_family quota_genl_family = {
1072 .id = GENL_ID_GENERATE,
1073 .hdrsize = 0,
1074 .name = "VFS_DQUOT",
1075 .version = 1,
1076 .maxattr = QUOTA_NL_A_MAX,
1077};
1078
1079/* Send warning to userspace about user which exceeded quota */
1080static void send_warning(const struct dquot *dquot, const char warntype)
1081{
1082 static atomic_t seq;
1083 struct sk_buff *skb;
1084 void *msg_head;
1085 int ret;
1086 int msg_size = 4 * nla_total_size(sizeof(u32)) +
1087 2 * nla_total_size(sizeof(u64));
1088
1089 /* We have to allocate using GFP_NOFS as we are called from a
1090 * filesystem performing write and thus further recursion into
1091 * the fs to free some data could cause deadlocks. */
1092 skb = genlmsg_new(msg_size, GFP_NOFS);
1093 if (!skb) {
1094 printk(KERN_ERR
1095 "VFS: Not enough memory to send quota warning.\n");
1096 return;
1097 }
1098 msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
1099 &quota_genl_family, 0, QUOTA_NL_C_WARNING);
1100 if (!msg_head) {
1101 printk(KERN_ERR
1102 "VFS: Cannot store netlink header in quota warning.\n");
1103 goto err_out;
1104 }
1105 ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, dquot->dq_type);
1106 if (ret)
1107 goto attr_err_out;
1108 ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, dquot->dq_id);
1109 if (ret)
1110 goto attr_err_out;
1111 ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
1112 if (ret)
1113 goto attr_err_out;
1114 ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR,
1115 MAJOR(dquot->dq_sb->s_dev));
1116 if (ret)
1117 goto attr_err_out;
1118 ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR,
1119 MINOR(dquot->dq_sb->s_dev));
1120 if (ret)
1121 goto attr_err_out;
1122 ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
1123 if (ret)
1124 goto attr_err_out;
1125 genlmsg_end(skb, msg_head);
1126
1127 genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
1128 return;
1129attr_err_out:
1130 printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
1131err_out:
1132 kfree_skb(skb);
1133}
1134#endif
1135/*
1136 * Write warnings to the console and send warning messages over netlink.
1137 *
1138 * Note that this function can sleep.
1139 */
1140static void flush_warnings(struct dquot *const *dquots, char *warntype)
1141{
1142 int i;
1143
1144 for (i = 0; i < MAXQUOTAS; i++)
1145 if (dquots[i] && warntype[i] != QUOTA_NL_NOWARN &&
1146 !warning_issued(dquots[i], warntype[i])) {
1147#ifdef CONFIG_PRINT_QUOTA_WARNING
1148 print_warning(dquots[i], warntype[i]);
1149#endif
1150#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
1151 send_warning(dquots[i], warntype[i]);
1152#endif
1153 }
1154}
1155
1156static int ignore_hardlimit(struct dquot *dquot)
1157{
1158 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
1159
1160 return capable(CAP_SYS_RESOURCE) &&
1161 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD ||
1162 !(info->dqi_flags & V1_DQF_RSQUASH));
1163}
1164
1165/* needs dq_data_lock */
1166static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype)
1167{
1168 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes;
1169
1170 *warntype = QUOTA_NL_NOWARN;
1171 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) ||
1172 test_bit(DQ_FAKE_B, &dquot->dq_flags))
1173 return QUOTA_OK;
1174
1175 if (dquot->dq_dqb.dqb_ihardlimit &&
1176 newinodes > dquot->dq_dqb.dqb_ihardlimit &&
1177 !ignore_hardlimit(dquot)) {
1178 *warntype = QUOTA_NL_IHARDWARN;
1179 return NO_QUOTA;
1180 }
1181
1182 if (dquot->dq_dqb.dqb_isoftlimit &&
1183 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1184 dquot->dq_dqb.dqb_itime &&
1185 get_seconds() >= dquot->dq_dqb.dqb_itime &&
1186 !ignore_hardlimit(dquot)) {
1187 *warntype = QUOTA_NL_ISOFTLONGWARN;
1188 return NO_QUOTA;
1189 }
1190
1191 if (dquot->dq_dqb.dqb_isoftlimit &&
1192 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1193 dquot->dq_dqb.dqb_itime == 0) {
1194 *warntype = QUOTA_NL_ISOFTWARN;
1195 dquot->dq_dqb.dqb_itime = get_seconds() +
1196 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
1197 }
1198
1199 return QUOTA_OK;
1200}
1201
1202/* needs dq_data_lock */
1203static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
1204{
1205 qsize_t tspace;
1206 struct super_block *sb = dquot->dq_sb;
1207
1208 *warntype = QUOTA_NL_NOWARN;
1209 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) ||
1210 test_bit(DQ_FAKE_B, &dquot->dq_flags))
1211 return QUOTA_OK;
1212
1213 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace
1214 + space;
1215
1216 if (dquot->dq_dqb.dqb_bhardlimit &&
1217 tspace > dquot->dq_dqb.dqb_bhardlimit &&
1218 !ignore_hardlimit(dquot)) {
1219 if (!prealloc)
1220 *warntype = QUOTA_NL_BHARDWARN;
1221 return NO_QUOTA;
1222 }
1223
1224 if (dquot->dq_dqb.dqb_bsoftlimit &&
1225 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1226 dquot->dq_dqb.dqb_btime &&
1227 get_seconds() >= dquot->dq_dqb.dqb_btime &&
1228 !ignore_hardlimit(dquot)) {
1229 if (!prealloc)
1230 *warntype = QUOTA_NL_BSOFTLONGWARN;
1231 return NO_QUOTA;
1232 }
1233
1234 if (dquot->dq_dqb.dqb_bsoftlimit &&
1235 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1236 dquot->dq_dqb.dqb_btime == 0) {
1237 if (!prealloc) {
1238 *warntype = QUOTA_NL_BSOFTWARN;
1239 dquot->dq_dqb.dqb_btime = get_seconds() +
1240 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace;
1241 }
1242 else
1243 /*
1244 * We don't allow preallocation to exceed softlimit so exceeding will
1245 * be always printed
1246 */
1247 return NO_QUOTA;
1248 }
1249
1250 return QUOTA_OK;
1251}
1252
1253static int info_idq_free(struct dquot *dquot, qsize_t inodes)
1254{
1255 qsize_t newinodes;
1256
1257 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
1258 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit ||
1259 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type))
1260 return QUOTA_NL_NOWARN;
1261
1262 newinodes = dquot->dq_dqb.dqb_curinodes - inodes;
1263 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit)
1264 return QUOTA_NL_ISOFTBELOW;
1265 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&
1266 newinodes < dquot->dq_dqb.dqb_ihardlimit)
1267 return QUOTA_NL_IHARDBELOW;
1268 return QUOTA_NL_NOWARN;
1269}
1270
1271static int info_bdq_free(struct dquot *dquot, qsize_t space)
1272{
1273 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
1274 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
1275 return QUOTA_NL_NOWARN;
1276
1277 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
1278 return QUOTA_NL_BSOFTBELOW;
1279 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit &&
1280 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit)
1281 return QUOTA_NL_BHARDBELOW;
1282 return QUOTA_NL_NOWARN;
1283}
1284/*
1285 * Initialize quota pointers in inode
1286 * We do things in a bit complicated way but by that we avoid calling
1287 * dqget() and thus filesystem callbacks under dqptr_sem.
1288 */
1289int dquot_initialize(struct inode *inode, int type)
1290{
1291 unsigned int id = 0;
1292 int cnt, ret = 0;
1293 struct dquot *got[MAXQUOTAS] = { NULL, NULL };
1294 struct super_block *sb = inode->i_sb;
1295
1296 /* First test before acquiring mutex - solves deadlocks when we
1297 * re-enter the quota code and are already holding the mutex */
1298 if (IS_NOQUOTA(inode))
1299 return 0;
1300
1301 /* First get references to structures we might need. */
1302 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1303 if (type != -1 && cnt != type)
1304 continue;
1305 switch (cnt) {
1306 case USRQUOTA:
1307 id = inode->i_uid;
1308 break;
1309 case GRPQUOTA:
1310 id = inode->i_gid;
1311 break;
1312 }
1313 got[cnt] = dqget(sb, id, cnt);
1314 }
1315
1316 down_write(&sb_dqopt(sb)->dqptr_sem);
1317 /* Having dqptr_sem we know NOQUOTA flags can't be altered... */
1318 if (IS_NOQUOTA(inode))
1319 goto out_err;
1320 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1321 if (type != -1 && cnt != type)
1322 continue;
1323 /* Avoid races with quotaoff() */
1324 if (!sb_has_quota_active(sb, cnt))
1325 continue;
1326 if (!inode->i_dquot[cnt]) {
1327 inode->i_dquot[cnt] = got[cnt];
1328 got[cnt] = NULL;
1329 }
1330 }
1331out_err:
1332 up_write(&sb_dqopt(sb)->dqptr_sem);
1333 /* Drop unused references */
1334 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1335 dqput(got[cnt]);
1336 return ret;
1337}
1338EXPORT_SYMBOL(dquot_initialize);
1339
1340/*
1341 * Release all quotas referenced by inode
1342 */
1343int dquot_drop(struct inode *inode)
1344{
1345 int cnt;
1346 struct dquot *put[MAXQUOTAS];
1347
1348 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1349 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1350 put[cnt] = inode->i_dquot[cnt];
1351 inode->i_dquot[cnt] = NULL;
1352 }
1353 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1354
1355 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1356 dqput(put[cnt]);
1357 return 0;
1358}
1359EXPORT_SYMBOL(dquot_drop);
1360
1361/* Wrapper to remove references to quota structures from inode */
1362void vfs_dq_drop(struct inode *inode)
1363{
1364 /* Here we can get arbitrary inode from clear_inode() so we have
1365 * to be careful. OTOH we don't need locking as quota operations
1366 * are allowed to change only at mount time */
1367 if (!IS_NOQUOTA(inode) && inode->i_sb && inode->i_sb->dq_op
1368 && inode->i_sb->dq_op->drop) {
1369 int cnt;
1370 /* Test before calling to rule out calls from proc and such
1371 * where we are not allowed to block. Note that this is
1372 * actually reliable test even without the lock - the caller
1373 * must assure that nobody can come after the DQUOT_DROP and
1374 * add quota pointers back anyway */
1375 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1376 if (inode->i_dquot[cnt])
1377 break;
1378 if (cnt < MAXQUOTAS)
1379 inode->i_sb->dq_op->drop(inode);
1380 }
1381}
1382EXPORT_SYMBOL(vfs_dq_drop);
1383
1384/*
1385 * Following four functions update i_blocks+i_bytes fields and
1386 * quota information (together with appropriate checks)
1387 * NOTE: We absolutely rely on the fact that caller dirties
1388 * the inode (usually macros in quotaops.h care about this) and
1389 * holds a handle for the current transaction so that dquot write and
1390 * inode write go into the same transaction.
1391 */
1392
1393/*
1394 * This operation can block, but only after everything is updated
1395 */
1396int __dquot_alloc_space(struct inode *inode, qsize_t number,
1397 int warn, int reserve)
1398{
1399 int cnt, ret = QUOTA_OK;
1400 char warntype[MAXQUOTAS];
1401
1402 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1403 warntype[cnt] = QUOTA_NL_NOWARN;
1404
1405 spin_lock(&dq_data_lock);
1406 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1407 if (!inode->i_dquot[cnt])
1408 continue;
1409 if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt)
1410 == NO_QUOTA) {
1411 ret = NO_QUOTA;
1412 goto out_unlock;
1413 }
1414 }
1415 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1416 if (!inode->i_dquot[cnt])
1417 continue;
1418 if (reserve)
1419 dquot_resv_space(inode->i_dquot[cnt], number);
1420 else
1421 dquot_incr_space(inode->i_dquot[cnt], number);
1422 }
1423 if (!reserve)
1424 inode_add_bytes(inode, number);
1425out_unlock:
1426 spin_unlock(&dq_data_lock);
1427 flush_warnings(inode->i_dquot, warntype);
1428 return ret;
1429}
1430
1431int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
1432{
1433 int cnt, ret = QUOTA_OK;
1434
1435 /*
1436 * First test before acquiring mutex - solves deadlocks when we
1437 * re-enter the quota code and are already holding the mutex
1438 */
1439 if (IS_NOQUOTA(inode)) {
1440 inode_add_bytes(inode, number);
1441 goto out;
1442 }
1443
1444 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1445 if (IS_NOQUOTA(inode)) {
1446 inode_add_bytes(inode, number);
1447 goto out_unlock;
1448 }
1449
1450 ret = __dquot_alloc_space(inode, number, warn, 0);
1451 if (ret == NO_QUOTA)
1452 goto out_unlock;
1453
1454 /* Dirtify all the dquots - this can block when journalling */
1455 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1456 if (inode->i_dquot[cnt])
1457 mark_dquot_dirty(inode->i_dquot[cnt]);
1458out_unlock:
1459 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1460out:
1461 return ret;
1462}
1463EXPORT_SYMBOL(dquot_alloc_space);
1464
1465int dquot_reserve_space(struct inode *inode, qsize_t number, int warn)
1466{
1467 int ret = QUOTA_OK;
1468
1469 if (IS_NOQUOTA(inode))
1470 goto out;
1471
1472 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1473 if (IS_NOQUOTA(inode))
1474 goto out_unlock;
1475
1476 ret = __dquot_alloc_space(inode, number, warn, 1);
1477out_unlock:
1478 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1479out:
1480 return ret;
1481}
1482EXPORT_SYMBOL(dquot_reserve_space);
1483
1484/*
1485 * This operation can block, but only after everything is updated
1486 */
1487int dquot_alloc_inode(const struct inode *inode, qsize_t number)
1488{
1489 int cnt, ret = NO_QUOTA;
1490 char warntype[MAXQUOTAS];
1491
1492 /* First test before acquiring mutex - solves deadlocks when we
1493 * re-enter the quota code and are already holding the mutex */
1494 if (IS_NOQUOTA(inode))
1495 return QUOTA_OK;
1496 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1497 warntype[cnt] = QUOTA_NL_NOWARN;
1498 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1499 if (IS_NOQUOTA(inode)) {
1500 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1501 return QUOTA_OK;
1502 }
1503 spin_lock(&dq_data_lock);
1504 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1505 if (!inode->i_dquot[cnt])
1506 continue;
1507 if (check_idq(inode->i_dquot[cnt], number, warntype+cnt)
1508 == NO_QUOTA)
1509 goto warn_put_all;
1510 }
1511
1512 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1513 if (!inode->i_dquot[cnt])
1514 continue;
1515 dquot_incr_inodes(inode->i_dquot[cnt], number);
1516 }
1517 ret = QUOTA_OK;
1518warn_put_all:
1519 spin_unlock(&dq_data_lock);
1520 if (ret == QUOTA_OK)
1521 /* Dirtify all the dquots - this can block when journalling */
1522 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1523 if (inode->i_dquot[cnt])
1524 mark_dquot_dirty(inode->i_dquot[cnt]);
1525 flush_warnings(inode->i_dquot, warntype);
1526 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1527 return ret;
1528}
1529EXPORT_SYMBOL(dquot_alloc_inode);
1530
1531int dquot_claim_space(struct inode *inode, qsize_t number)
1532{
1533 int cnt;
1534 int ret = QUOTA_OK;
1535
1536 if (IS_NOQUOTA(inode)) {
1537 inode_add_bytes(inode, number);
1538 goto out;
1539 }
1540
1541 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1542 if (IS_NOQUOTA(inode)) {
1543 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1544 inode_add_bytes(inode, number);
1545 goto out;
1546 }
1547
1548 spin_lock(&dq_data_lock);
1549 /* Claim reserved quotas to allocated quotas */
1550 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1551 if (inode->i_dquot[cnt])
1552 dquot_claim_reserved_space(inode->i_dquot[cnt],
1553 number);
1554 }
1555 /* Update inode bytes */
1556 inode_add_bytes(inode, number);
1557 spin_unlock(&dq_data_lock);
1558 /* Dirtify all the dquots - this can block when journalling */
1559 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1560 if (inode->i_dquot[cnt])
1561 mark_dquot_dirty(inode->i_dquot[cnt]);
1562 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1563out:
1564 return ret;
1565}
1566EXPORT_SYMBOL(dquot_claim_space);
1567
1568/*
1569 * Release reserved quota space
1570 */
1571void dquot_release_reserved_space(struct inode *inode, qsize_t number)
1572{
1573 int cnt;
1574
1575 if (IS_NOQUOTA(inode))
1576 goto out;
1577
1578 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1579 if (IS_NOQUOTA(inode))
1580 goto out_unlock;
1581
1582 spin_lock(&dq_data_lock);
1583 /* Release reserved dquots */
1584 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1585 if (inode->i_dquot[cnt])
1586 dquot_free_reserved_space(inode->i_dquot[cnt], number);
1587 }
1588 spin_unlock(&dq_data_lock);
1589
1590out_unlock:
1591 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1592out:
1593 return;
1594}
1595EXPORT_SYMBOL(dquot_release_reserved_space);
1596
1597/*
1598 * This operation can block, but only after everything is updated
1599 */
1600int dquot_free_space(struct inode *inode, qsize_t number)
1601{
1602 unsigned int cnt;
1603 char warntype[MAXQUOTAS];
1604
1605 /* First test before acquiring mutex - solves deadlocks when we
1606 * re-enter the quota code and are already holding the mutex */
1607 if (IS_NOQUOTA(inode)) {
1608out_sub:
1609 inode_sub_bytes(inode, number);
1610 return QUOTA_OK;
1611 }
1612
1613 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1614 /* Now recheck reliably when holding dqptr_sem */
1615 if (IS_NOQUOTA(inode)) {
1616 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1617 goto out_sub;
1618 }
1619 spin_lock(&dq_data_lock);
1620 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1621 if (!inode->i_dquot[cnt])
1622 continue;
1623 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number);
1624 dquot_decr_space(inode->i_dquot[cnt], number);
1625 }
1626 inode_sub_bytes(inode, number);
1627 spin_unlock(&dq_data_lock);
1628 /* Dirtify all the dquots - this can block when journalling */
1629 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1630 if (inode->i_dquot[cnt])
1631 mark_dquot_dirty(inode->i_dquot[cnt]);
1632 flush_warnings(inode->i_dquot, warntype);
1633 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1634 return QUOTA_OK;
1635}
1636EXPORT_SYMBOL(dquot_free_space);
1637
1638/*
1639 * This operation can block, but only after everything is updated
1640 */
1641int dquot_free_inode(const struct inode *inode, qsize_t number)
1642{
1643 unsigned int cnt;
1644 char warntype[MAXQUOTAS];
1645
1646 /* First test before acquiring mutex - solves deadlocks when we
1647 * re-enter the quota code and are already holding the mutex */
1648 if (IS_NOQUOTA(inode))
1649 return QUOTA_OK;
1650
1651 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1652 /* Now recheck reliably when holding dqptr_sem */
1653 if (IS_NOQUOTA(inode)) {
1654 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1655 return QUOTA_OK;
1656 }
1657 spin_lock(&dq_data_lock);
1658 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1659 if (!inode->i_dquot[cnt])
1660 continue;
1661 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], number);
1662 dquot_decr_inodes(inode->i_dquot[cnt], number);
1663 }
1664 spin_unlock(&dq_data_lock);
1665 /* Dirtify all the dquots - this can block when journalling */
1666 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1667 if (inode->i_dquot[cnt])
1668 mark_dquot_dirty(inode->i_dquot[cnt]);
1669 flush_warnings(inode->i_dquot, warntype);
1670 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1671 return QUOTA_OK;
1672}
1673EXPORT_SYMBOL(dquot_free_inode);
1674
1675/*
1676 * call back function, get reserved quota space from underlying fs
1677 */
1678qsize_t dquot_get_reserved_space(struct inode *inode)
1679{
1680 qsize_t reserved_space = 0;
1681
1682 if (sb_any_quota_active(inode->i_sb) &&
1683 inode->i_sb->dq_op->get_reserved_space)
1684 reserved_space = inode->i_sb->dq_op->get_reserved_space(inode);
1685 return reserved_space;
1686}
1687
1688/*
1689 * Transfer the number of inode and blocks from one diskquota to an other.
1690 *
1691 * This operation can block, but only after everything is updated
1692 * A transaction must be started when entering this function.
1693 */
1694int dquot_transfer(struct inode *inode, struct iattr *iattr)
1695{
1696 qsize_t space, cur_space;
1697 qsize_t rsv_space = 0;
1698 struct dquot *transfer_from[MAXQUOTAS];
1699 struct dquot *transfer_to[MAXQUOTAS];
1700 int cnt, ret = QUOTA_OK;
1701 int chuid = iattr->ia_valid & ATTR_UID && inode->i_uid != iattr->ia_uid,
1702 chgid = iattr->ia_valid & ATTR_GID && inode->i_gid != iattr->ia_gid;
1703 char warntype_to[MAXQUOTAS];
1704 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS];
1705
1706 /* First test before acquiring mutex - solves deadlocks when we
1707 * re-enter the quota code and are already holding the mutex */
1708 if (IS_NOQUOTA(inode))
1709 return QUOTA_OK;
1710 /* Initialize the arrays */
1711 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1712 transfer_from[cnt] = NULL;
1713 transfer_to[cnt] = NULL;
1714 warntype_to[cnt] = QUOTA_NL_NOWARN;
1715 }
1716 if (chuid)
1717 transfer_to[USRQUOTA] = dqget(inode->i_sb, iattr->ia_uid,
1718 USRQUOTA);
1719 if (chgid)
1720 transfer_to[GRPQUOTA] = dqget(inode->i_sb, iattr->ia_gid,
1721 GRPQUOTA);
1722
1723 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1724 /* Now recheck reliably when holding dqptr_sem */
1725 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
1726 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1727 goto put_all;
1728 }
1729 spin_lock(&dq_data_lock);
1730 cur_space = inode_get_bytes(inode);
1731 rsv_space = dquot_get_reserved_space(inode);
1732 space = cur_space + rsv_space;
1733 /* Build the transfer_from list and check the limits */
1734 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1735 if (!transfer_to[cnt])
1736 continue;
1737 transfer_from[cnt] = inode->i_dquot[cnt];
1738 if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) ==
1739 NO_QUOTA || check_bdq(transfer_to[cnt], space, 0,
1740 warntype_to + cnt) == NO_QUOTA)
1741 goto over_quota;
1742 }
1743
1744 /*
1745 * Finally perform the needed transfer from transfer_from to transfer_to
1746 */
1747 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1748 /*
1749 * Skip changes for same uid or gid or for turned off quota-type.
1750 */
1751 if (!transfer_to[cnt])
1752 continue;
1753
1754 /* Due to IO error we might not have transfer_from[] structure */
1755 if (transfer_from[cnt]) {
1756 warntype_from_inodes[cnt] =
1757 info_idq_free(transfer_from[cnt], 1);
1758 warntype_from_space[cnt] =
1759 info_bdq_free(transfer_from[cnt], space);
1760 dquot_decr_inodes(transfer_from[cnt], 1);
1761 dquot_decr_space(transfer_from[cnt], cur_space);
1762 dquot_free_reserved_space(transfer_from[cnt],
1763 rsv_space);
1764 }
1765
1766 dquot_incr_inodes(transfer_to[cnt], 1);
1767 dquot_incr_space(transfer_to[cnt], cur_space);
1768 dquot_resv_space(transfer_to[cnt], rsv_space);
1769
1770 inode->i_dquot[cnt] = transfer_to[cnt];
1771 }
1772 spin_unlock(&dq_data_lock);
1773 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1774
1775 /* Dirtify all the dquots - this can block when journalling */
1776 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1777 if (transfer_from[cnt])
1778 mark_dquot_dirty(transfer_from[cnt]);
1779 if (transfer_to[cnt]) {
1780 mark_dquot_dirty(transfer_to[cnt]);
1781 /* The reference we got is transferred to the inode */
1782 transfer_to[cnt] = NULL;
1783 }
1784 }
1785warn_put_all:
1786 flush_warnings(transfer_to, warntype_to);
1787 flush_warnings(transfer_from, warntype_from_inodes);
1788 flush_warnings(transfer_from, warntype_from_space);
1789put_all:
1790 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1791 dqput(transfer_from[cnt]);
1792 dqput(transfer_to[cnt]);
1793 }
1794 return ret;
1795over_quota:
1796 spin_unlock(&dq_data_lock);
1797 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1798 /* Clear dquot pointers we don't want to dqput() */
1799 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1800 transfer_from[cnt] = NULL;
1801 ret = NO_QUOTA;
1802 goto warn_put_all;
1803}
1804EXPORT_SYMBOL(dquot_transfer);
1805
1806/* Wrapper for transferring ownership of an inode */
1807int vfs_dq_transfer(struct inode *inode, struct iattr *iattr)
1808{
1809 if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) {
1810 vfs_dq_init(inode);
1811 if (inode->i_sb->dq_op->transfer(inode, iattr) == NO_QUOTA)
1812 return 1;
1813 }
1814 return 0;
1815}
1816EXPORT_SYMBOL(vfs_dq_transfer);
1817
1818/*
1819 * Write info of quota file to disk
1820 */
1821int dquot_commit_info(struct super_block *sb, int type)
1822{
1823 int ret;
1824 struct quota_info *dqopt = sb_dqopt(sb);
1825
1826 mutex_lock(&dqopt->dqio_mutex);
1827 ret = dqopt->ops[type]->write_file_info(sb, type);
1828 mutex_unlock(&dqopt->dqio_mutex);
1829 return ret;
1830}
1831EXPORT_SYMBOL(dquot_commit_info);
1832
1833/*
1834 * Definitions of diskquota operations.
1835 */
1836struct dquot_operations dquot_operations = {
1837 .initialize = dquot_initialize,
1838 .drop = dquot_drop,
1839 .alloc_space = dquot_alloc_space,
1840 .alloc_inode = dquot_alloc_inode,
1841 .free_space = dquot_free_space,
1842 .free_inode = dquot_free_inode,
1843 .transfer = dquot_transfer,
1844 .write_dquot = dquot_commit,
1845 .acquire_dquot = dquot_acquire,
1846 .release_dquot = dquot_release,
1847 .mark_dirty = dquot_mark_dquot_dirty,
1848 .write_info = dquot_commit_info,
1849 .alloc_dquot = dquot_alloc,
1850 .destroy_dquot = dquot_destroy,
1851};
1852
1853/*
1854 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
1855 */
1856int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags)
1857{
1858 int cnt, ret = 0;
1859 struct quota_info *dqopt = sb_dqopt(sb);
1860 struct inode *toputinode[MAXQUOTAS];
1861
1862 /* Cannot turn off usage accounting without turning off limits, or
1863 * suspend quotas and simultaneously turn quotas off. */
1864 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED))
1865 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED |
1866 DQUOT_USAGE_ENABLED)))
1867 return -EINVAL;
1868
1869 /* We need to serialize quota_off() for device */
1870 mutex_lock(&dqopt->dqonoff_mutex);
1871
1872 /*
1873 * Skip everything if there's nothing to do. We have to do this because
1874 * sometimes we are called when fill_super() failed and calling
1875 * sync_fs() in such cases does no good.
1876 */
1877 if (!sb_any_quota_loaded(sb)) {
1878 mutex_unlock(&dqopt->dqonoff_mutex);
1879 return 0;
1880 }
1881 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1882 toputinode[cnt] = NULL;
1883 if (type != -1 && cnt != type)
1884 continue;
1885 if (!sb_has_quota_loaded(sb, cnt))
1886 continue;
1887
1888 if (flags & DQUOT_SUSPENDED) {
1889 spin_lock(&dq_state_lock);
1890 dqopt->flags |=
1891 dquot_state_flag(DQUOT_SUSPENDED, cnt);
1892 spin_unlock(&dq_state_lock);
1893 } else {
1894 spin_lock(&dq_state_lock);
1895 dqopt->flags &= ~dquot_state_flag(flags, cnt);
1896 /* Turning off suspended quotas? */
1897 if (!sb_has_quota_loaded(sb, cnt) &&
1898 sb_has_quota_suspended(sb, cnt)) {
1899 dqopt->flags &= ~dquot_state_flag(
1900 DQUOT_SUSPENDED, cnt);
1901 spin_unlock(&dq_state_lock);
1902 iput(dqopt->files[cnt]);
1903 dqopt->files[cnt] = NULL;
1904 continue;
1905 }
1906 spin_unlock(&dq_state_lock);
1907 }
1908
1909 /* We still have to keep quota loaded? */
1910 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED))
1911 continue;
1912
1913 /* Note: these are blocking operations */
1914 drop_dquot_ref(sb, cnt);
1915 invalidate_dquots(sb, cnt);
1916 /*
1917 * Now all dquots should be invalidated, all writes done so we
1918 * should be only users of the info. No locks needed.
1919 */
1920 if (info_dirty(&dqopt->info[cnt]))
1921 sb->dq_op->write_info(sb, cnt);
1922 if (dqopt->ops[cnt]->free_file_info)
1923 dqopt->ops[cnt]->free_file_info(sb, cnt);
1924 put_quota_format(dqopt->info[cnt].dqi_format);
1925
1926 toputinode[cnt] = dqopt->files[cnt];
1927 if (!sb_has_quota_loaded(sb, cnt))
1928 dqopt->files[cnt] = NULL;
1929 dqopt->info[cnt].dqi_flags = 0;
1930 dqopt->info[cnt].dqi_igrace = 0;
1931 dqopt->info[cnt].dqi_bgrace = 0;
1932 dqopt->ops[cnt] = NULL;
1933 }
1934 mutex_unlock(&dqopt->dqonoff_mutex);
1935
1936 /* Skip syncing and setting flags if quota files are hidden */
1937 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
1938 goto put_inodes;
1939
1940 /* Sync the superblock so that buffers with quota data are written to
1941 * disk (and so userspace sees correct data afterwards). */
1942 if (sb->s_op->sync_fs)
1943 sb->s_op->sync_fs(sb, 1);
1944 sync_blockdev(sb->s_bdev);
1945 /* Now the quota files are just ordinary files and we can set the
1946 * inode flags back. Moreover we discard the pagecache so that
1947 * userspace sees the writes we did bypassing the pagecache. We
1948 * must also discard the blockdev buffers so that we see the
1949 * changes done by userspace on the next quotaon() */
1950 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1951 if (toputinode[cnt]) {
1952 mutex_lock(&dqopt->dqonoff_mutex);
1953 /* If quota was reenabled in the meantime, we have
1954 * nothing to do */
1955 if (!sb_has_quota_loaded(sb, cnt)) {
1956 mutex_lock_nested(&toputinode[cnt]->i_mutex,
1957 I_MUTEX_QUOTA);
1958 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
1959 S_NOATIME | S_NOQUOTA);
1960 truncate_inode_pages(&toputinode[cnt]->i_data,
1961 0);
1962 mutex_unlock(&toputinode[cnt]->i_mutex);
1963 mark_inode_dirty(toputinode[cnt]);
1964 }
1965 mutex_unlock(&dqopt->dqonoff_mutex);
1966 }
1967 if (sb->s_bdev)
1968 invalidate_bdev(sb->s_bdev);
1969put_inodes:
1970 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1971 if (toputinode[cnt]) {
1972 /* On remount RO, we keep the inode pointer so that we
1973 * can reenable quota on the subsequent remount RW. We
1974 * have to check 'flags' variable and not use sb_has_
1975 * function because another quotaon / quotaoff could
1976 * change global state before we got here. We refuse
1977 * to suspend quotas when there is pending delete on
1978 * the quota file... */
1979 if (!(flags & DQUOT_SUSPENDED))
1980 iput(toputinode[cnt]);
1981 else if (!toputinode[cnt]->i_nlink)
1982 ret = -EBUSY;
1983 }
1984 return ret;
1985}
1986EXPORT_SYMBOL(vfs_quota_disable);
1987
1988int vfs_quota_off(struct super_block *sb, int type, int remount)
1989{
1990 return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED :
1991 (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED));
1992}
1993EXPORT_SYMBOL(vfs_quota_off);
1994/*
1995 * Turn quotas on on a device
1996 */
1997
1998/*
1999 * Helper function to turn quotas on when we already have the inode of
2000 * quota file and no quota information is loaded.
2001 */
2002static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
2003 unsigned int flags)
2004{
2005 struct quota_format_type *fmt = find_quota_format(format_id);
2006 struct super_block *sb = inode->i_sb;
2007 struct quota_info *dqopt = sb_dqopt(sb);
2008 int error;
2009 int oldflags = -1;
2010
2011 if (!fmt)
2012 return -ESRCH;
2013 if (!S_ISREG(inode->i_mode)) {
2014 error = -EACCES;
2015 goto out_fmt;
2016 }
2017 if (IS_RDONLY(inode)) {
2018 error = -EROFS;
2019 goto out_fmt;
2020 }
2021 if (!sb->s_op->quota_write || !sb->s_op->quota_read) {
2022 error = -EINVAL;
2023 goto out_fmt;
2024 }
2025 /* Usage always has to be set... */
2026 if (!(flags & DQUOT_USAGE_ENABLED)) {
2027 error = -EINVAL;
2028 goto out_fmt;
2029 }
2030
2031 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2032 /* As we bypass the pagecache we must now flush the inode so
2033 * that we see all the changes from userspace... */
2034 write_inode_now(inode, 1);
2035 /* And now flush the block cache so that kernel sees the
2036 * changes */
2037 invalidate_bdev(sb->s_bdev);
2038 }
2039 mutex_lock(&inode->i_mutex);
2040 mutex_lock(&dqopt->dqonoff_mutex);
2041 if (sb_has_quota_loaded(sb, type)) {
2042 error = -EBUSY;
2043 goto out_lock;
2044 }
2045
2046 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2047 /* We don't want quota and atime on quota files (deadlocks
2048 * possible) Also nobody should write to the file - we use
2049 * special IO operations which ignore the immutable bit. */
2050 down_write(&dqopt->dqptr_sem);
2051 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE |
2052 S_NOQUOTA);
2053 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
2054 up_write(&dqopt->dqptr_sem);
2055 sb->dq_op->drop(inode);
2056 }
2057
2058 error = -EIO;
2059 dqopt->files[type] = igrab(inode);
2060 if (!dqopt->files[type])
2061 goto out_lock;
2062 error = -EINVAL;
2063 if (!fmt->qf_ops->check_quota_file(sb, type))
2064 goto out_file_init;
2065
2066 dqopt->ops[type] = fmt->qf_ops;
2067 dqopt->info[type].dqi_format = fmt;
2068 dqopt->info[type].dqi_fmt_id = format_id;
2069 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
2070 mutex_lock(&dqopt->dqio_mutex);
2071 error = dqopt->ops[type]->read_file_info(sb, type);
2072 if (error < 0) {
2073 mutex_unlock(&dqopt->dqio_mutex);
2074 goto out_file_init;
2075 }
2076 mutex_unlock(&dqopt->dqio_mutex);
2077 mutex_unlock(&inode->i_mutex);
2078 spin_lock(&dq_state_lock);
2079 dqopt->flags |= dquot_state_flag(flags, type);
2080 spin_unlock(&dq_state_lock);
2081
2082 add_dquot_ref(sb, type);
2083 mutex_unlock(&dqopt->dqonoff_mutex);
2084
2085 return 0;
2086
2087out_file_init:
2088 dqopt->files[type] = NULL;
2089 iput(inode);
2090out_lock:
2091 mutex_unlock(&dqopt->dqonoff_mutex);
2092 if (oldflags != -1) {
2093 down_write(&dqopt->dqptr_sem);
2094 /* Set the flags back (in the case of accidental quotaon()
2095 * on a wrong file we don't want to mess up the flags) */
2096 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
2097 inode->i_flags |= oldflags;
2098 up_write(&dqopt->dqptr_sem);
2099 }
2100 mutex_unlock(&inode->i_mutex);
2101out_fmt:
2102 put_quota_format(fmt);
2103
2104 return error;
2105}
2106
2107/* Reenable quotas on remount RW */
2108static int vfs_quota_on_remount(struct super_block *sb, int type)
2109{
2110 struct quota_info *dqopt = sb_dqopt(sb);
2111 struct inode *inode;
2112 int ret;
2113 unsigned int flags;
2114
2115 mutex_lock(&dqopt->dqonoff_mutex);
2116 if (!sb_has_quota_suspended(sb, type)) {
2117 mutex_unlock(&dqopt->dqonoff_mutex);
2118 return 0;
2119 }
2120 inode = dqopt->files[type];
2121 dqopt->files[type] = NULL;
2122 spin_lock(&dq_state_lock);
2123 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
2124 DQUOT_LIMITS_ENABLED, type);
2125 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type);
2126 spin_unlock(&dq_state_lock);
2127 mutex_unlock(&dqopt->dqonoff_mutex);
2128
2129 flags = dquot_generic_flag(flags, type);
2130 ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id,
2131 flags);
2132 iput(inode);
2133
2134 return ret;
2135}
2136
2137int vfs_quota_on_path(struct super_block *sb, int type, int format_id,
2138 struct path *path)
2139{
2140 int error = security_quota_on(path->dentry);
2141 if (error)
2142 return error;
2143 /* Quota file not on the same filesystem? */
2144 if (path->mnt->mnt_sb != sb)
2145 error = -EXDEV;
2146 else
2147 error = vfs_load_quota_inode(path->dentry->d_inode, type,
2148 format_id, DQUOT_USAGE_ENABLED |
2149 DQUOT_LIMITS_ENABLED);
2150 return error;
2151}
2152EXPORT_SYMBOL(vfs_quota_on_path);
2153
2154int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name,
2155 int remount)
2156{
2157 struct path path;
2158 int error;
2159
2160 if (remount)
2161 return vfs_quota_on_remount(sb, type);
2162
2163 error = kern_path(name, LOOKUP_FOLLOW, &path);
2164 if (!error) {
2165 error = vfs_quota_on_path(sb, type, format_id, &path);
2166 path_put(&path);
2167 }
2168 return error;
2169}
2170EXPORT_SYMBOL(vfs_quota_on);
2171
2172/*
2173 * More powerful function for turning on quotas allowing setting
2174 * of individual quota flags
2175 */
2176int vfs_quota_enable(struct inode *inode, int type, int format_id,
2177 unsigned int flags)
2178{
2179 int ret = 0;
2180 struct super_block *sb = inode->i_sb;
2181 struct quota_info *dqopt = sb_dqopt(sb);
2182
2183 /* Just unsuspend quotas? */
2184 if (flags & DQUOT_SUSPENDED)
2185 return vfs_quota_on_remount(sb, type);
2186 if (!flags)
2187 return 0;
2188 /* Just updating flags needed? */
2189 if (sb_has_quota_loaded(sb, type)) {
2190 mutex_lock(&dqopt->dqonoff_mutex);
2191 /* Now do a reliable test... */
2192 if (!sb_has_quota_loaded(sb, type)) {
2193 mutex_unlock(&dqopt->dqonoff_mutex);
2194 goto load_quota;
2195 }
2196 if (flags & DQUOT_USAGE_ENABLED &&
2197 sb_has_quota_usage_enabled(sb, type)) {
2198 ret = -EBUSY;
2199 goto out_lock;
2200 }
2201 if (flags & DQUOT_LIMITS_ENABLED &&
2202 sb_has_quota_limits_enabled(sb, type)) {
2203 ret = -EBUSY;
2204 goto out_lock;
2205 }
2206 spin_lock(&dq_state_lock);
2207 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type);
2208 spin_unlock(&dq_state_lock);
2209out_lock:
2210 mutex_unlock(&dqopt->dqonoff_mutex);
2211 return ret;
2212 }
2213
2214load_quota:
2215 return vfs_load_quota_inode(inode, type, format_id, flags);
2216}
2217EXPORT_SYMBOL(vfs_quota_enable);
2218
2219/*
2220 * This function is used when filesystem needs to initialize quotas
2221 * during mount time.
2222 */
2223int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
2224 int format_id, int type)
2225{
2226 struct dentry *dentry;
2227 int error;
2228
2229 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
2230 if (IS_ERR(dentry))
2231 return PTR_ERR(dentry);
2232
2233 if (!dentry->d_inode) {
2234 error = -ENOENT;
2235 goto out;
2236 }
2237
2238 error = security_quota_on(dentry);
2239 if (!error)
2240 error = vfs_load_quota_inode(dentry->d_inode, type, format_id,
2241 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
2242
2243out:
2244 dput(dentry);
2245 return error;
2246}
2247EXPORT_SYMBOL(vfs_quota_on_mount);
2248
2249/* Wrapper to turn on quotas when remounting rw */
2250int vfs_dq_quota_on_remount(struct super_block *sb)
2251{
2252 int cnt;
2253 int ret = 0, err;
2254
2255 if (!sb->s_qcop || !sb->s_qcop->quota_on)
2256 return -ENOSYS;
2257 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2258 err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1);
2259 if (err < 0 && !ret)
2260 ret = err;
2261 }
2262 return ret;
2263}
2264EXPORT_SYMBOL(vfs_dq_quota_on_remount);
2265
2266static inline qsize_t qbtos(qsize_t blocks)
2267{
2268 return blocks << QIF_DQBLKSIZE_BITS;
2269}
2270
2271static inline qsize_t stoqb(qsize_t space)
2272{
2273 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
2274}
2275
2276/* Generic routine for getting common part of quota structure */
2277static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
2278{
2279 struct mem_dqblk *dm = &dquot->dq_dqb;
2280
2281 spin_lock(&dq_data_lock);
2282 di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit);
2283 di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit);
2284 di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace;
2285 di->dqb_ihardlimit = dm->dqb_ihardlimit;
2286 di->dqb_isoftlimit = dm->dqb_isoftlimit;
2287 di->dqb_curinodes = dm->dqb_curinodes;
2288 di->dqb_btime = dm->dqb_btime;
2289 di->dqb_itime = dm->dqb_itime;
2290 di->dqb_valid = QIF_ALL;
2291 spin_unlock(&dq_data_lock);
2292}
2293
2294int vfs_get_dqblk(struct super_block *sb, int type, qid_t id,
2295 struct if_dqblk *di)
2296{
2297 struct dquot *dquot;
2298
2299 dquot = dqget(sb, id, type);
2300 if (!dquot)
2301 return -ESRCH;
2302 do_get_dqblk(dquot, di);
2303 dqput(dquot);
2304
2305 return 0;
2306}
2307EXPORT_SYMBOL(vfs_get_dqblk);
2308
2309/* Generic routine for setting common part of quota structure */
2310static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
2311{
2312 struct mem_dqblk *dm = &dquot->dq_dqb;
2313 int check_blim = 0, check_ilim = 0;
2314 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
2315
2316 if ((di->dqb_valid & QIF_BLIMITS &&
2317 (di->dqb_bhardlimit > dqi->dqi_maxblimit ||
2318 di->dqb_bsoftlimit > dqi->dqi_maxblimit)) ||
2319 (di->dqb_valid & QIF_ILIMITS &&
2320 (di->dqb_ihardlimit > dqi->dqi_maxilimit ||
2321 di->dqb_isoftlimit > dqi->dqi_maxilimit)))
2322 return -ERANGE;
2323
2324 spin_lock(&dq_data_lock);
2325 if (di->dqb_valid & QIF_SPACE) {
2326 dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace;
2327 check_blim = 1;
2328 __set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
2329 }
2330 if (di->dqb_valid & QIF_BLIMITS) {
2331 dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
2332 dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
2333 check_blim = 1;
2334 __set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
2335 }
2336 if (di->dqb_valid & QIF_INODES) {
2337 dm->dqb_curinodes = di->dqb_curinodes;
2338 check_ilim = 1;
2339 __set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
2340 }
2341 if (di->dqb_valid & QIF_ILIMITS) {
2342 dm->dqb_isoftlimit = di->dqb_isoftlimit;
2343 dm->dqb_ihardlimit = di->dqb_ihardlimit;
2344 check_ilim = 1;
2345 __set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
2346 }
2347 if (di->dqb_valid & QIF_BTIME) {
2348 dm->dqb_btime = di->dqb_btime;
2349 check_blim = 1;
2350 __set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
2351 }
2352 if (di->dqb_valid & QIF_ITIME) {
2353 dm->dqb_itime = di->dqb_itime;
2354 check_ilim = 1;
2355 __set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
2356 }
2357
2358 if (check_blim) {
2359 if (!dm->dqb_bsoftlimit ||
2360 dm->dqb_curspace < dm->dqb_bsoftlimit) {
2361 dm->dqb_btime = 0;
2362 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
2363 } else if (!(di->dqb_valid & QIF_BTIME))
2364 /* Set grace only if user hasn't provided his own... */
2365 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace;
2366 }
2367 if (check_ilim) {
2368 if (!dm->dqb_isoftlimit ||
2369 dm->dqb_curinodes < dm->dqb_isoftlimit) {
2370 dm->dqb_itime = 0;
2371 clear_bit(DQ_INODES_B, &dquot->dq_flags);
2372 } else if (!(di->dqb_valid & QIF_ITIME))
2373 /* Set grace only if user hasn't provided his own... */
2374 dm->dqb_itime = get_seconds() + dqi->dqi_igrace;
2375 }
2376 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit ||
2377 dm->dqb_isoftlimit)
2378 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
2379 else
2380 set_bit(DQ_FAKE_B, &dquot->dq_flags);
2381 spin_unlock(&dq_data_lock);
2382 mark_dquot_dirty(dquot);
2383
2384 return 0;
2385}
2386
2387int vfs_set_dqblk(struct super_block *sb, int type, qid_t id,
2388 struct if_dqblk *di)
2389{
2390 struct dquot *dquot;
2391 int rc;
2392
2393 dquot = dqget(sb, id, type);
2394 if (!dquot) {
2395 rc = -ESRCH;
2396 goto out;
2397 }
2398 rc = do_set_dqblk(dquot, di);
2399 dqput(dquot);
2400out:
2401 return rc;
2402}
2403EXPORT_SYMBOL(vfs_set_dqblk);
2404
2405/* Generic routine for getting common part of quota file information */
2406int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
2407{
2408 struct mem_dqinfo *mi;
2409
2410 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
2411 if (!sb_has_quota_active(sb, type)) {
2412 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
2413 return -ESRCH;
2414 }
2415 mi = sb_dqopt(sb)->info + type;
2416 spin_lock(&dq_data_lock);
2417 ii->dqi_bgrace = mi->dqi_bgrace;
2418 ii->dqi_igrace = mi->dqi_igrace;
2419 ii->dqi_flags = mi->dqi_flags & DQF_MASK;
2420 ii->dqi_valid = IIF_ALL;
2421 spin_unlock(&dq_data_lock);
2422 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
2423 return 0;
2424}
2425EXPORT_SYMBOL(vfs_get_dqinfo);
2426
2427/* Generic routine for setting common part of quota file information */
2428int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
2429{
2430 struct mem_dqinfo *mi;
2431 int err = 0;
2432
2433 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
2434 if (!sb_has_quota_active(sb, type)) {
2435 err = -ESRCH;
2436 goto out;
2437 }
2438 mi = sb_dqopt(sb)->info + type;
2439 spin_lock(&dq_data_lock);
2440 if (ii->dqi_valid & IIF_BGRACE)
2441 mi->dqi_bgrace = ii->dqi_bgrace;
2442 if (ii->dqi_valid & IIF_IGRACE)
2443 mi->dqi_igrace = ii->dqi_igrace;
2444 if (ii->dqi_valid & IIF_FLAGS)
2445 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) |
2446 (ii->dqi_flags & DQF_MASK);
2447 spin_unlock(&dq_data_lock);
2448 mark_info_dirty(sb, type);
2449 /* Force write to disk */
2450 sb->dq_op->write_info(sb, type);
2451out:
2452 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
2453 return err;
2454}
2455EXPORT_SYMBOL(vfs_set_dqinfo);
2456
2457struct quotactl_ops vfs_quotactl_ops = {
2458 .quota_on = vfs_quota_on,
2459 .quota_off = vfs_quota_off,
2460 .quota_sync = vfs_quota_sync,
2461 .get_info = vfs_get_dqinfo,
2462 .set_info = vfs_set_dqinfo,
2463 .get_dqblk = vfs_get_dqblk,
2464 .set_dqblk = vfs_set_dqblk
2465};
2466
2467static ctl_table fs_dqstats_table[] = {
2468 {
2469 .ctl_name = FS_DQ_LOOKUPS,
2470 .procname = "lookups",
2471 .data = &dqstats.lookups,
2472 .maxlen = sizeof(int),
2473 .mode = 0444,
2474 .proc_handler = &proc_dointvec,
2475 },
2476 {
2477 .ctl_name = FS_DQ_DROPS,
2478 .procname = "drops",
2479 .data = &dqstats.drops,
2480 .maxlen = sizeof(int),
2481 .mode = 0444,
2482 .proc_handler = &proc_dointvec,
2483 },
2484 {
2485 .ctl_name = FS_DQ_READS,
2486 .procname = "reads",
2487 .data = &dqstats.reads,
2488 .maxlen = sizeof(int),
2489 .mode = 0444,
2490 .proc_handler = &proc_dointvec,
2491 },
2492 {
2493 .ctl_name = FS_DQ_WRITES,
2494 .procname = "writes",
2495 .data = &dqstats.writes,
2496 .maxlen = sizeof(int),
2497 .mode = 0444,
2498 .proc_handler = &proc_dointvec,
2499 },
2500 {
2501 .ctl_name = FS_DQ_CACHE_HITS,
2502 .procname = "cache_hits",
2503 .data = &dqstats.cache_hits,
2504 .maxlen = sizeof(int),
2505 .mode = 0444,
2506 .proc_handler = &proc_dointvec,
2507 },
2508 {
2509 .ctl_name = FS_DQ_ALLOCATED,
2510 .procname = "allocated_dquots",
2511 .data = &dqstats.allocated_dquots,
2512 .maxlen = sizeof(int),
2513 .mode = 0444,
2514 .proc_handler = &proc_dointvec,
2515 },
2516 {
2517 .ctl_name = FS_DQ_FREE,
2518 .procname = "free_dquots",
2519 .data = &dqstats.free_dquots,
2520 .maxlen = sizeof(int),
2521 .mode = 0444,
2522 .proc_handler = &proc_dointvec,
2523 },
2524 {
2525 .ctl_name = FS_DQ_SYNCS,
2526 .procname = "syncs",
2527 .data = &dqstats.syncs,
2528 .maxlen = sizeof(int),
2529 .mode = 0444,
2530 .proc_handler = &proc_dointvec,
2531 },
2532#ifdef CONFIG_PRINT_QUOTA_WARNING
2533 {
2534 .ctl_name = FS_DQ_WARNINGS,
2535 .procname = "warnings",
2536 .data = &flag_print_warnings,
2537 .maxlen = sizeof(int),
2538 .mode = 0644,
2539 .proc_handler = &proc_dointvec,
2540 },
2541#endif
2542 { .ctl_name = 0 },
2543};
2544
2545static ctl_table fs_table[] = {
2546 {
2547 .ctl_name = FS_DQSTATS,
2548 .procname = "quota",
2549 .mode = 0555,
2550 .child = fs_dqstats_table,
2551 },
2552 { .ctl_name = 0 },
2553};
2554
2555static ctl_table sys_table[] = {
2556 {
2557 .ctl_name = CTL_FS,
2558 .procname = "fs",
2559 .mode = 0555,
2560 .child = fs_table,
2561 },
2562 { .ctl_name = 0 },
2563};
2564
2565static int __init dquot_init(void)
2566{
2567 int i;
2568 unsigned long nr_hash, order;
2569
2570 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
2571
2572 register_sysctl_table(sys_table);
2573
2574 dquot_cachep = kmem_cache_create("dquot",
2575 sizeof(struct dquot), sizeof(unsigned long) * 4,
2576 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
2577 SLAB_MEM_SPREAD|SLAB_PANIC),
2578 NULL);
2579
2580 order = 0;
2581 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
2582 if (!dquot_hash)
2583 panic("Cannot create dquot hash table");
2584
2585 /* Find power-of-two hlist_heads which can fit into allocation */
2586 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
2587 dq_hash_bits = 0;
2588 do {
2589 dq_hash_bits++;
2590 } while (nr_hash >> dq_hash_bits);
2591 dq_hash_bits--;
2592
2593 nr_hash = 1UL << dq_hash_bits;
2594 dq_hash_mask = nr_hash - 1;
2595 for (i = 0; i < nr_hash; i++)
2596 INIT_HLIST_HEAD(dquot_hash + i);
2597
2598 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
2599 nr_hash, order, (PAGE_SIZE << order));
2600
2601 register_shrinker(&dqcache_shrinker);
2602
2603#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
2604 if (genl_register_family(&quota_genl_family) != 0)
2605 printk(KERN_ERR
2606 "VFS: Failed to create quota netlink interface.\n");
2607#endif
2608
2609 return 0;
2610}
2611module_init(dquot_init);
generated by cgit v1.2.2 (git 2.25.0) at 2024-09-21 02:47:06 -0400